// 退税用换汇成本计算公式
// Currency exchange cost
var currencyExchangeCost = {
	data:{
		amount:0,
		tax:0.17,
		drawback:0.17,
		fob:0
	},
	output:function(){
		return (this.data.amount * (1 + (this.data.tax - this.data.drawback))) / this.data.fob;
	}
};
